The present invention relates generally to a biopsy collecting system, and more specifically to a biopsy collecting needle and guard assembly.
In the biopsy field, needles are frequently employed to gather or otherwise collect specimens for laboratory examination. The surgical procedure frequently requires that the surgeon be fully aware of the depth of penetration of the needle in order that a proper specimen be obtained. Since the outer surface of the biopsy specimen collecting needle is preferably smooth and polished, it is difficult to employ spaced markings along the surface of the needle so as to indicate depth of penetration of the tip. In accordance with the present invention, a sleeve guard has been designed which performs a dual function, the first being a sealing of the needle portion of the structure from the ambient, the second being the utilization of the guard as an indicator of the depth of penetration of the needle.
The biopsy specimen collecting needle is conventional, and may be, for example, designed in accordance with that certain claimed in U.S. Pat. No. 3,938,505 or, as an alternative, that certain biopsy specimen collecting device disclosed and claimed in U.S. Pat. No. 3,882,849. In addition, a substantial number of other devices of this type are commercially available.
The sleeve guard element is fabricated from a frangible brittle material which, upon being scored, can be broken upon flexure. Therefore, in actual operation, the sleeve guard is placed over the tubular needle, with the upper end of the sleeve guard being arranged in sealing engagement with the outer periphery of the aspirating chamber, and specifically about the outer periphery of the needle hub. The outer circumference of the shank of the sleeve guard has a plurality of spaced apart circumferential grooves formed therein and disposed at spaced intervals along the length of the guard shank. These spaced score grooves are formed to a depth sufficient to permit the shank to be broken upon flexure so as to form an open ended sleeve exposing a predetermined portion of the tubular needle. The end surface of the broken guard therefore forms a base which functions as a stop for the needle upon entering the body of the patient from which the specimen is being obtained. Therefore, prior to use the guard forms a sealed enclosure for the needle, and subsequently, upon being broken in preparation for use of the specimen collecting system, the guard is broken off to the predetermined depth, thereby exposing the desired length of tubular needle required to perform the specimen collecting operation.